The mediating effect of sleep quality on solid cooking fuel use and psychological distress among rural older adults: evidence from Shandong, China

Exposure to indoor air pollution from solid cooking fuel use may increase mental disorders risk through pathways such as oroxidative stress, neuroinflammation, or cerebrovascular damage. However, few studies have explored the underlying mechanism between solid cooking fuel use and psychological distress. The present study aims to investigate the mediating role of sleep quality on the relationship between solid cooking fuel use and psychological distress among older adults in rural Shandong, China. This study used the cross-sectional data from the second follow-up survey of the Shandong Rural Elderly Health Cohort (SREHC). A total of 3,240 rural older adults were included in the analysis. Logistic regression and the Karlson, Holm, and Breen (KHB) mediation analyses were performed to investigate the relationship between solid cooking fuel use and psychological distress, as well as the mediating role of sleep quality in this association. This study found that solid cooking fuel use was significantly and positively associated with psychological distress among older adults in rural Shandong, China (OR = 1.38, 95% CI: 1.12,1.70). Mediation analysis revealed that sleep quality mediated the association between solid cooking fuel use and psychological distress among older adults (β = 0.06, P = 0.011). The mediation effect accounted for 16.18% of the total effect. Our study showed that solid cooking fuel use was associated with psychological distress among rural older adults, and sleep quality mediated this association. Interventions should focus on addressing cooking fuel types and poor sleep quality to reduce psychological distress. In the future, more aggressive environmental protection policies would be needed to lessen the adverse effects of indoor air pollution on the health of older adults in rural China.